How can I set a customized currency symbol to be applied to a number?

The biggest misconception here is that DecimalFormat will automatically format to currency
values. This is not the case; the basic DecimalFormat will assume that it is strictly
formating just a number. You need to use NumberFormat.getCurrencyInstance(), which returns a NumberFormat. In general, the NumberFormat will also be a DecimalFormat, but it knows to
format a value as currency. The other minor error is that setMonetaryDecimalSeparator( char
sep ) needs to be used instead of setDecimalSeparator(char decimalSeparator).

Of course, a large amount of work has been done with these classes, including locales, to
avoid customization, but the following code shows how I would do it when necessary: